ITV this morning officially announced that Brent Montgomery, founder and CEO of ITV-owned Leftfield Entertainment, has been appointed CEO of ITV Studios U.S. Group, which is being renamed ITV America. ITV Studios acquired a controlling stake in Leftfield last year. As part of today’s restructuring, ITV has acquired the remaining 20% of the Leftfield Entertainment group.

Montgomery will oversee ITV’s U.S. group of businesses, which collectively produce over 100 programs on 43 networks, the vast majority of them on the unscripted side. The list of the ITV American companies include production arm ITV Studios America, which will be rebranded as ITV Entertainment, as well as acquired companies Leftfield Pictures, Sirens Media, Outpost Entertainment, Loud TV, Riot Creative, Thinkfactory Media, High Noon Entertainment, DiGa and Gurney Productions. They will continue to produce under their current labels and with their existing management teams under the ITV America umbrella.

Montgomery will report to Kevin Lygo, Managing Director, ITV Studios. Also reporting to Lygo is recently appointed Philippe Maigret, President of ITV America’s scripted business, who will work with Montgomery. The top ITV Studios US Group post had been vacant since chairman Paul Buccieri left a year ago to join A+E Networks.

Montgomery is the latest reality producer to sell his company to a European content company and eventually become head of the mothership company’s U.S. outpost. The list also includes Cris Abrego and Charlie Corwin, whose 51 Minds and Original Media were bought by Endemol, with the duo becoming co-CEOs of Endemol North America and later co-CEOs of Endemol Shine North America. And Thom Beers of FremantleMedia-owned Original Prods. became CEO of FremantleMedia North America.

Several key executives Montgomery worked with at Leftfield also are getting bigger responsibilities at the umbrella company. Leftfield’s Chief Creative Officer Adam Sher will serve in the same capacity at ITV America; Leftfield’s General Manager Chris Valentini becomes Chief Operating Officer of ITV America, and Ed Simpson transitions from Leftfield Entertainment to become EVP, Business Development & International, ITV America. Meanwhile, Leftfield’s president David George will succeed Montgomery as CEO of that company. Valentini, George and Simpson all remain based in New York, with Sher continuing to operate out of Los Angeles.

The heads of all ITV America production companies will continue to lead their respective businesses, reporting to Montgomery. A head of the rebranded, Los Angeles-based ITV Entertainment, will be named shortly, with Sher overseeing it in the interim. Several executives are staying put. Oliver De La Hoz remains EVP, Finance; Ivan Garel-Jones remains EVP, Business and Legal Affairs; and Jenise Caiola remains EVP, Human Resources, all at ITV America.

“ITV has gone from strength to strength in the U.S. over the last few years both organically and through acquisition and is now the biggest unscripted indie in the U.S.,” Lygo said. “Bringing all our U.S. production businesses together, ITV America will build on this success as we take our U.S. operations to the next level and continue to build a global content business of scale.”

Selling his first series in 2008, Montgomery formed Leftfield Pictures the following year, quickly growing the business to what is now Leftfield Entertainment, which this year produced 364 hours of content, including hit franchise Pawn Stars, and series American Restoration and Counting Cars. Recent commissions include Killing Fields, Food Porn, Brain Surgery Live, Arctic Recovery and He Shed, She Shed.